This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 2000-333914, filed Oct. 31, 2000; and No. 2001-290118, filed Sep. 21, 2001, the entire contents of both of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to method for manufacturing a semiconductor device using a stencil mask, a stencil mask used the method for manufacturing a semiconductor device, and method for manufacturing the stencil mask.
2. Description of the Related Art
There is a method in which a stencil mask (or an aperture) having an opening is set at a certain distance on a substrate and an ion implantation is carried out, in a manufacturing process of a semiconductor device, in a process where a MOSFET in which its electrically conductive types of a channel within the same substrate are different or a MOSFET in which its threshold voltages are different is manufactured, when an ion implantation of an impurity is carried out into a well, a channel or Poly-Si.
In the case where a stencil mask is used in the ion implantation process in the manufacturing for a semiconductor device, it is carried out by employing a stencil mask having an opening limited to a region for ion implantation of the object of a substrate to be processed. Specifically, in the desired ion implantation region, ions are implanted through the opening of a stencil mask, and in a region for non-ion implantation, ions are shielded by a stencil mask shielding portion. However, on the stencil mask for shielding an ion, shielded ions are accumulated by repetitive ion implantations. Damages are also accumulated by shielded ions repeatedly crushing. As a result, after a plurality of ion implantation processes, the stencil mask is deformed and the ion implantation cannot be carried out with a high precision for positions.
For example, as shown in FIG. 39, when an impurity ion 4204 is implanted into a Si substrate 4201 on which an isolation region 4202 is formed through the opening of a stencil mask 4203 interspatially installed, if a distortion is generated on the stencil mask 4203, since the position of the opening is displaced, an ion implantation region 4205 is not formed over the whole desired region, and a non-ion implantation region 4206 is formed. Moreover, depending on the shape of rough coating pattern, a problem is occurred that an n-type impurity is implanted over to a region in which a p-type region is to be formed.
As a result, the electric characteristics of a manufactured semiconductor product are varied, or the product poorly operates. Therefore, a stencil mask becomes unusable after it is used in the process of a plurality of ion implantations. The cost of manufacturing a stencil mask is converted to the cost of a manufacturing a semiconductor device, it leads to the rise of the manufacturing cost of the semiconductor device.
Moreover, in the case of a stencil mask employing a SOI substrate, since it is shielded by a thin film portion region having an opening and a supporting portion for supporting the thin film portion region in which the oxide film is an insulating film, its electrical conductivity and thermal conductivity are poor, and when it is used in the manufacturing process of a semiconductor, there has been a problem that the deformation due to the heat occurs or the ability of pattern formation is lowered due to the accumulation of charges.
By the way, in the manufacturing for a semiconductor device employing charged particles represented by ion implantation process, it is required that the desired particles uniformly reach to the region of the object. Therefore, it is needed that the uniformity is confirmed, that is, the amount of particles is measured by spatial separation, and when it does not have the desired uniformity, the uniformity should be maintained by performing the adjustment of the particle generation source within the apparatus for manufacturing a semiconductor device and the transport system of the particles on the basis of the measured signal. Moreover, in order to maintain the uniformity of the processing state among a plurality of processing substrates, it is required that the amount of particles reaching to the processing substrate is finely and precisely measured.
For the confirmation of this uniformity and the definition of the number of the particles reached to the substrate, there is a method of confirming the state of the substrate to be processed using another measurement device by actually performing the processing to the substrate to be processed. However, in this case, since the time is taken from the processing to the measurement, it is difficult to readjust the device on the basis of the result.
Therefore, it is desirable that the measurement for the uniformity is performed within the device, the re-adjustment of the device is performed on the basis of the measurement of the results and the uniformity is measured again. For the measurement of the uniformity within the device, there is a method of evaluating the uniformity by measuring the output from the probes, for example, such as Faraday gauges or the like arranged in lines for measuring the electric charge amount of the particles passing through the specific region.
However, since these probes measure the valence electrons, any information concerning with the neutralized particles cannot be obtained. On the other hand, for example, in the ion implantation process, an ion may be neutralized due to the influence of the residual gas in the device, and the neutralized particles also act similarly as the ion does to the substrate to be processed. Therefore, a probe capable of measuring particles including the neutral particles has been required. Moreover, it has been desired that the spatial resolution is enhanced upon the measurement along with the miniaturization and refinement of a semiconductor element, however, it has been difficult to miniaturize a probe for it.
As described above, it has been desired that in-plane distribution of the number of the neutral particles and the charged particles reached to the semiconductor substrate is measured and the number of particles reached to the semiconductor substrate is precisely controlled.
As described above, in the case where a stencil mask is used in the ion implantation process a plurality of times, the distortion of the mask is generated, and the ion implantation position with respect to the semiconductor substrate is deviated, thereby making the electric characteristics of the semiconductor products to be varied or making the product poorly operate. Therefore, in order to lower the manufacturing cost of the semiconductor device, a stencil mask capable of being made in a cheap cost or a stencil mask having a long life has been desired.
Moreover, there has been a problem that an ability of pattern formation is lowered due to the deformation with heat and the accumulation of electric charges caused by electrification.
A device for measurement capable of measuring an in-plane distribution of the number of the neutral particles and the charged particles reached to the substrate has been required.
The present invention is configured so as to achieve the above-described objects as the followings.
(1) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: a method for manufacturing a semiconductor device comprising: preparing a stencil mask comprising a silicon thin film in which an opening for selectively irradiating charged particles to a semiconductor substrate is provided and whose irradiation surface on which the charged particles are irradiated is implanted with an impurity; and selectively irradiating charged particles to the semiconductor substrate using the stencil mask which is opposingly arranged on the semiconductor substrate.
(2) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: preparing a stencil mask comprising a metal thin film in which an opening for selectively irradiating charged particles to a semiconductor substrate is formed and a semiconductor layer formed on an irradiation surface of the metal thin film on which the charged particles are irradiated; and selectively irradiating charged particles to a semiconductor substrate using the stencil mask which is opposingly arranged on the semiconductor substrate.
(3) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: preparing a stencil mask comprising a thin film in which an opening for selectively irradiating charged particles to a semiconductor substrate is formed and a plurality of covering layers formed on a surface of the thin film; and selectively irradiating charged particles to a semiconductor substrate using the stencil mask which is opposingly arranged on the semiconductor substrate.
(4) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: preparing a stencil a mask comprising a silicon thin film in which an opening for selectively irradiating charged particles to a semiconductor substrate is formed and an insulating layer formed on an irradiation surface of the silicon thin film on which the charged particles are irradiated; and selectively irradiating charged particles to a semiconductor substrate using the stencil mask which is opposingly arranged on the semiconductor substrate.
(5) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: preparing a stencil mask comprising a shielding film in which an opening for selectively irradiating charged particles to a semiconductor substrate is formed and an resist film formed on an irradiation surface of the shielding film on which the charged particles are irradiated; and selectively irradiating charged particles to a semiconductor substrate using the stencil mask which is opposingly arranged on the semiconductor substrate.
(6) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: selectively forming a first resist film on an irradiation surface of the shielding film on which charged particles are irradiated to a stencil mask having the shielding film in which an opening through which charged particles pass is provided; selectively irradiating charged particles to one or more sheets of semiconductor substrates using the stencil mask comprising the first resist film; removing a resist formed on an irradiation surface of the stencil mask; selectively forming a second resist film on an irradiation surface of the shielding film on which the charged particles are irradiated; and selectively irradiating charged particles to the semiconductor substrate once or more.
(7) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: preparing a stencil mask comprising a thin film provided with an opening for selectively irradiating charged particles to a semiconductor substrate, depth of the opening being different corresponding to the size of the opening; and selectively irradiating charged particles to a semiconductor substrate using the stencil mask which is opposingly arranged on the semiconductor substrate.
(8) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: preparing a stencil mask comprising a thin film in which an opening for selectively irradiating charged particles to a semiconductor substrate is provided, an insulating layer which is formed on an irradiation surface of the thin film on which the charged particles are irradiated and a supporting substrate which is formed on the thin film and the insulating layer and which is conductive to the thin film; selectively irradiating charged particles to the semiconductor substrate using the stencil mask which is opposingly arranged on a semiconductor substrate; and discharging the charged particles attached to the thin film from the stencil mask via the supporting substrate by irradiation of the charged particles.
(9) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device comprising: selectively implanting ions to a semiconductor substrate by irradiating charged particles to the semiconductor substrate via a stencil mask comprising a thin film opposingly arranged on the semiconductor substrate and having an opening; and adjusting a potential difference between the thin film and the semiconductor substrate during irradiation of the charged particles.
(10) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device in which particle beam including ions and neutral particles of impurity are irradiated to a semiconductor substrate installed at an irradiation position and an impurity of implantation amount D per unit area is implanted to the semiconductor substrate, the method comprising: irradiating the particle beam to a particle amount measurement device comprising an electron generation/discharging device which is installed nearby the irradiation position in a state where the semiconductor substrate is not irradiated by the particle beam and which generates and amplifies electrons corresponding to an incident position of ions and neutral particles incident to a measurement surface and discharges the electrons from back surface side, an electron detector for measuring a position and an amount of electrons discharged from the electron generation/discharging device, and a particle amount calculation section for calculating a distribution of total particle amount of ions and neutral particles incident to a surface of the particle detector from positions and amount of electrons measured by the electron detector and irradiating the particle beam and to a beam current measurement device installed at a position different from the irradiation position for measuring current by the ions; measuring an in-plane distribution of a total particle amount of the ions and neutral particles of particle beam irradiated to the electron generation/discharging device using the particle amount measurement device; controlling an in-plane distribution of a total particle amount by adjusting a generating system for generating the particle beam and a transporting system through which the generated particle beam pass; moving the semiconductor substrate to the irradiation position; and irradiating the particle beam to the semiconductor substrate.
(11) According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor device in which particle beam including ions and neutral particles of impurity are irradiated to a semiconductor substrate installed at an irradiation position and an impurity of implantation amount D per unit area is implanted to the semiconductor substrate, the method comprising: irradiating the particle beam to a particle amount measurement device comprising an electron generation/discharging device which is installed nearby the irradiation position in a state where the semiconductor substrate is not irradiated by particle beam and which generates and amplifies electrons corresponding to an incident position of ions and neutral particles incident to a measurement surface and discharges the electrons from back surface side, an electron detector for measuring a position and an amount of electrons discharged from the electron generation/discharging device, and a particle amount calculation section for calculating a distribution of total particle amount of ions and neutral particles incident to a surface of the particle detector from positions and amount of electrons measured by the electron detector and irradiating the particle beam and to a beam current measurement device installed at a position different from the irradiation position for measuring current by the ions; finding an ion amount N2 per unit area incident to the beam current measurement device from a current measured by the beam current measurement device as well as measuring total amount of particles N of ions and neutral particles incident to unit area of the measurement surface by the particle amount measurement device; finding conversion value D2=Dxc3x97(N2/N) from the total amount of particles N, the amount of ions N2 and the amount of impurity D; installing the semiconductor substrate to the irradiation position; irradiating particle beam to the semiconductor substrate to implanted an impurity into the semiconductor substrate; measuring a current due to the ions by the beam current measurement device during implantation of the impurity and finding the amount of ions N2xe2x80x2 from measured current; and terminating the implantation of the impurity when the amount of ions N2xe2x80x2 and the conversion value D2 become equal to each other.
(12) According to one aspect of the present invention, there is provided a stencil mask comprising a silicon thin film in which an opening is formed, wherein an impurity is implanted into a surface of the silicon thin film.
(13) According to one aspect of the present invention, there is provided a stencil mask comprising: a metal thin film in which an opening is formed; a semiconductor layer formed on a surface of the metal thin film.
(14) According to one aspect of the present invention, there is provided a stencil mask comprising: a thin film in which an opening is formed; and a plurality of covering layers formed on a surface of the thin film.
(15) According to one aspect of the present invention, there is provided a stencil mask which used for an ion implantation process using a silicon thin film in which an opening is formed, wherein an insulating layer is formed on a surface of the silicon thin film.
(16) According to one aspect of the present invention, there is provided a stencil mask comprising: a thin film in which an opening through which charged particles pass is provided; and a resist film formed on an irradiation surface of the thin film on which the charged particles are irradiated.
(17) According to one aspect of the present invention, there is provided a stencil mask comprising: a thin film in which an opening through which charged particles pass is provided, the depth of the opening being different corresponding to the size of the opening.
(18) According to one aspect of the present invention, there is provided a stencil mask comprising: a thin film in which an opening for selectively irradiating charged particles to a substrate to be processed; an insulating layer formed on an irradiation surface of the thin film on which the charged particles are irradiated; and a supporting substrate formed on the thin film and the insulating layer and conductive to the thin film.
(19) According to one aspect of the present invention, there is provided a method for manufacturing a stencil mask, comprising: implanting an impurity into a surface side of a silicon thin film in which an opening is formed; and heating the silicon thin film.
(20) According to one aspect of the present invention, there is provided a method for manufacturing a stencil mask comprising: implanting an impurity into a silicon thin film surface of a SOI substrate in which a supporting substrate, an insulating layer and a silicon thin layer are stacked; patterning the silicon thin film and forming an opening through which the insulating layer is exposed on a bottom of the silicon thin film; and removing one portion of the supporting substrate and the insulating layer and exposing a bottom surface of an opening.
(21) According to one aspect of the present invention, there is provided a method for manufacturing a stencil mask comprising: implanting an impurity into one surface of a silicon substrate; heating the silicon substrate; joining a surface to which an impurity is implanted and an insulating layer formed on a supporting substrate; grinding the silicon substrate to form a silicon thin film; patterning the silicon thin film and forming an opening through which the insulating layer is exposed; implanting an impurity to a surface of the silicon thin film; heating the silicon thin film; and removing one portion of the supporting substrate and the insulating layer and exposing a bottom surface of the opening.